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<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>CSS实现三角形</title>
</head>

<body>
    <h1>实现三角形的三种方式</h1>
    <div class="flex-container">
        <div class="item">
            <div class="border-full">
            </div>
            <span>border实现:三角全视角</span>
        </div>
        <div class="item">
            <div class="left" id="left" onclick="ltLib.toggle()">
            </div>
            <span>border实现:左三角</span>
        </div>
        <div class="item">
            <div class="up">
            </div>
            <span>border实现:上三角</span>
        </div>
        <div class="item">
            <div class="right">
            </div>
            <span>border实现:右三角</span>
        </div>
        <div class="item">
            <div class="bottom">
            </div>
            <span class="subTitle">border实现:下三角</span>
        </div>
    </div>
</body>

</html>